Gary Teale is struggling to be fit for Scotland's Euro 2008 qualifier with France on Wednesday.
The midfielder, who started the weekend's 3-1 win over Lithuania, has fallen ill after meeting up with his family following Saturday's game.
He did not travel with the rest of his Scotland team-mates to Paris on Tuesday ahead of the match between Group B's top two.
Though Teale could still link up with the squad ahead of Wednesday's fixture, it appears unlikely he will be fit to retain his place.
Meanwhile, Scotland coach Alex McLeish has given a hint as to his tactics for the clash with France.
McLeish said: "France are the home team, they are expected to win. It's like Scotland playing against Lithuania at the weekend.
"We have slipped up in recent years, but we are now winning against teams like Lithuania, so that reinforces the players' confidence."
France will be missing the suspended Thierry Henry, but McLeish is still aware the hosts have sufficient options to replace the Barcelona striker.
"They have good players," said McLeish. "They will miss Henry, he is a match-winner, but we know they have quality to bring in."